Fig. 2From: Solar spectral management for natural photosynthesis: from photonics designs to potential applicationsa Three photoluminescence processes employed in spectral converters and b Schematic illustration of the spectral conversion material with flat designs. The re-emitted photons in the spectral conversion materials either escape from the light escape cone (rays 1 and 2) or are trapped in the materials (rays 3 and 4) due to total internal reflectionBack to article page